I have to develop a project that basically receives and sends data on a Bluetooth LE module, and then changes the stream a bit and re-sends or receives that information on another radio module in the same case. The frequencies will be different. The Bluetooth needs to only transcieve a few feet, but the other frequency will have a somewhat longer range, probably 2 to 4 miles. I plan to have the modules physically on the same PC board, but on opposite ends. This will be in the US and possibly Canadian and EU / UK markets later.
I plan to use a 4 layer PC board of about 4 x 3 inches. It will be powered by rechargeable Lithium battery so I need to to run it on about 3.5 to 4 volts.
I had planned to use a PCB antenna for the BTLE but maybe an attachable antenna to the module for the other radio.
Are there many special issues I'll need to look out for when using two radios at once?
What other gotchas will I have to look out for? If I use modules that are both already certified with the FCC will I still need to receive intentional radiator certification? or just passive radiator?
I don't believe this is the same as this question this question because I'm going to use a lower frequency for the other radio, possibly the ISM bands.
There will not be two Bluetooth modules on the same board.